[Evolutionary epidemiological thought on infections].

The objective of the study is to analyse the main aspects of current epidemiological knowledge on the evolutionary status of infections. Living organisms in the biosphere are part of dynamic systems of variable intensities. Some of these systems are on the surface while others take place inside the genome core. Parasitism is a phenomenon commonly seen in nature. Infective parasites relate to each other through several mechanisms, such as genetic DNA exchange, and because of the connections established communities of infectious agents are not isolated. The internalization process allows the parasites to get into their hosts' cells, which is accomplished through the phagocytosis of infectious agents or other more sophisticated mechanisms such as pill production. To leave the intracellular medium, some organisms make use of apoptosis, a highly specialized genetic mechanism that makes possible to destroy macrophages. It is currently accepted that molecular DNA can flow into the blood stream as the so-called infectrons. Thus it is hypothesized the existence of infection networks that allows the coadaptability of parasites and their hosts, and creates coevolutionary forces between hosts and their parasites facilitating the emergence of new pathogens.